selftest: Make as_canonicalization_tests.py easier to run outside "make test"
This takes the realm from the LDAP base DN and so avoids one
easy mistake to make. So far the NT4 domain name is not
auto-detected, so much be read from the smb.conf.
By using .guess() the smb.conf is read for the unspecified
parts (eg workstation for an NTLM login to the LDAP server if
the target server is an IP address).
Signed-off-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Gary Lockyer <gary@catalyst.net.nz>